If my memory is correct, I had read that the 'uptick' rule was implemented to prevent traders from jumping in on a stock that was in the midst of a horrible downward spiral.

The uptick rule requires at least one up tick of the stock before you can short sell it. Also, you cannot short some stocks because the shares you are shorting have to be borrowed, and some stocks just don't have any available.

I also heard that the uptick rule was recently removed. Most people don't short sell anyways but if you be careful not to get squeezed too badly if the stock turns against you.

...The uptick rule requires at least one up tick of the stock before you can short sell it. Also, you cannot short some stocks because the shares you are shorting have to be borrowed, and some stocks just don't have any available.
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